Portion of a keyboard



FIG. 1 is a perspective view of a portion of a keyboard having a gradient surface appearance showing my new design;

FIG. 2 is a perspective view of the design with an area shown in dashed lines;

FIG. 3 is an enlarged view of the area shown in dashed lines in FIG. 2;

FIG. 4 is a top view of the design;

FIG. 5 is a front view thereof;

FIG. 6 is an enlarged left side view thereof;

FIG. 7 is an enlarged right side view thereof;

FIG. 8 is a rear view thereof; and,

FIG. 9 is a bottom view thereof.

The broken line showing of the remainder of the keyboard is included for the purpose of illustrating unclaimed portions of the article and forms no part of the claimed design. The dash-dot line adjacent to the gradient surface is an unclaimed boundary line. 

The ornamental design for a portion of a keyboard, as shown and described. 